PS363 Lecture Notes - Lecture 7: Olfactory System, Olfactory Bulb, Olfactory Receptor
Document Summary
In addition to perceive odours, smell is also a mode of communication. Chemicals released by the body, called pheromones, are important signals for reproductive behaviours, and they may also be used to mark territories, identify individuals, and indicate aggression or submission. We smell with a small, thin sheet of cells high up in the nasal cavity called the olfactory epithelium (fig. Olfactory receptor cells are the site of transduction. These are genuine neurons, with axons of their own that penetrate into the nervous system. Supporting cells are similar to glia and help produce mucus. Basal cells are a source of new receptor cells. Olfactory receptors continually grow, die, and regenerate, in a cycle that lasts about 4-8 weeks. Sniffing brings air through the nasal passages, but only a small percentage of that air passes over the olfactory epithelium. The epithelium exudes a thin coat of mucus containing antibodies, enzymes, and odorant binding proteins.
